The '59 Caddy Septic System

I was chatting with a friend the other day. He's a realtor & told me a story from the late '90's. He had sold a place and the buyer's bank required a septic system certification. After fruitlessly looking for the thing with shovels, a backhoe was hired in & started digging. He got a call to "come see this!" and saw the most amazing septic tank ever seen.
A previous owner of the place had dug a really large hole and pushed into it a 1959 Cadillac--tail fins and all! Then the waste material pipe from the house was run into the Caddy's trunk, the windows rolled down and the whole thing covered back over. The solids stayed in the car and the liquid flowed out the rolled down windows.
Ingenious, yes. Up to code?--not hardly!